Side drill



Jan. 23, 1951 A. ARUTUNOFF SIDE DRILL Filed June Illia. .l2

Patented Jan. 23, 1951 UNITED STATES PATENT OFFICE SIDE DRILL ArmaisArutunof, Bartlesville, Okla.

Application June 17, 1946, Serial No. 677,196

(Cl. Z55- 1.6)

12 Claims. 1 The present invention relates in general to drillingapparatus and more particularly to side drills for oil wells or boreholes of similar character.

It often is desirable to extend an existing well by drilling auxiliaryholes at an angle from the vertical bore hole either for the purpose oftapping formations which do not communicate with the original bore hole,or for some other purpose. The usual way of producing such holes is tolire projectiles into the side wall from a gun lowered in the well.However, the depth of penetration which may be obtained by this methodnaturally depends upon the hardness of the material to be pierced, andas a practical matter has proved to be much too limited to be usefulwhere the formation is hard or where the cement behind the well casingis of considerable thickness.

It is the fundamental object of my invention therefore to provideapparatus by means of which a deeper penetration may be obtained.

Another object is to provide a side drill which may be advanced into theside wall to any desired depth and then halted, the extent of theadvance being registered at all times at the surface of the well.

Another object is to provide a side drill adapted kto be lowered into abore hole, together with novel apparatus for locking the drill unittightly in the bore hole when it is at the level to be a drilled.Another object is to provide apparatus in the side drill unit to assistin orientation of the bit.

Another object is to provide an arrangement for carrying uid to the bitof the drill unit at all times during its penetration into the sidewall.

Another object is to provide novel facilities for catching andcollecting the cuttings returned to the main or vertical bore hole bythe drilling apparatus.

Other objects and features of my invention will appear from thefollowing description.

In the accompanying drawings which form a part of the instantspecification and are to be read in conjunction therewith and in whichlike reference numerals are employed to indicate like parts of thevarious views,

, Fig. 1 is a View showing the upper portion of my side drill inlongitudinal cross section.

Fig. la is a view showing the lower portion of my side drill inlongitudinal cross section.

Fig. 2 is a sectional view taken along the line 2--2 of Fig. 1a,

Fig. 3 is an enlarged cross section of the bit,

Fig. 4 is a side elevation of a modified form of my drill, and

Fig. 5 is a view showing the modified form of drill from the bottom.

Referring more particularly to the'drawings, the housing for my sidedrill is made up in two units. The upper unit comprises a cylindricalshell II having rigidly affixed thereto a cap I2 and a bottom piece I3;the lower unit comprises a somewhat shorter cylindrical shell I4 whichin like fashion has immovably secured to it a flanged cap I5 and abottom piece I6. The flanged cap I5 of the lower unit is fastened to thebottom piece I3 of the upper unit by means of screws I8, joining the twounits to form a single rigid structure.

In the upper half of this structure is an electrical motor I9 having arather elongated cylindrical casing. The motor casing is adapted to moveaxially of its surrounding shell but it cannot rotate therein due to thepresence of a pair of longitudinal ribs or splines 20 on the inside ofthe shell which cooperate with a slotted collar 2I on the outside of themotor casing.

Above the motor casing and securely fastened thereto by screws 23 isanother generally cylindrical casing 24. This has a flattened side wall25 at its top, in which side wall the shaft 26 of a reel 2l isjournaled. A string or light cable wound on the reel has its free endsecured to a hook in the cap I2 so that it will cause the reel to turnas the casing 24 moves downwardly nside shell II. Through suitablereduction gearing this turns the shaft of a rheostat 28.

The wiring from the rheostat and motor I9, as well as that from a Selsynmotor equipped gyroscope 29, extends upwardly into a tube 30 and thencethrough the steel clad cable 3I to the surface. The tube 30 is rigidlyaixed to the cable at one end and to the casing 24 at its other end, andaccordingly moves up and down with the latter. A suitable packing glandis provided in cap I2 to prevent fluid from entering the top of the sidedrill unit around tube 30.

Insulating oil lls the chamber 32 and extends downwardly through thecentral opening in a disk-like separator 33 and thence through tube 34into the motor, which runs in oil. Below the separator 33 is a piston 35and a spring 36. The under side of the piston communicates with thespace outside casing 24 through two apertures 31, while the space 38above the piston communicates with the chamber 32 through a smallbreather hole 39 in separator 33. Accordingly the piston will move up ordown to compensate for differences in pressure which may exist betweenchamber 32 and the region outside the casing.

A tube 40 is rigidly affixed to the bottom of the motor casing I9 sothat it extends downwardly into the vertical sleeve 4| secured to thebottom piece I3. A stuffing box 42 at the upper end of sleeve 4I permitstube 40 to slide in and out of the sleeve but seals the junction againstthe passage of fluid.

In the lower portion of the side drill structure is a rigid tube 44curved as shown and communicating at its lower end with an opening 45 inthe wall of shell I4. This serves as a guide for a longitudinallymovable fiexible sleeve or casing 46, the upper end of which is securelyfastened to tube 40. Below tube 40 and encircling the flexible casing inthe region within sleeve 4I a. coiled spring 41. A flexible drive shaft48 extends upwardly inside the exible casing and at a point inside tube46 it is rigidly attached to the lower end of the motor shaft 49. Thusthe sleeve 4I and the tube 44 form rigid tubular guide means for theflexible shaft 48 and the exible sheath or casing 46.

Referring to Fig. 3 it will be noted that the hollow shank I of a bitmember 52 is secured to the end of the drive shaft 48. This shank isjournaled in a thrust member 53 which is fastened tightly to the end ofthe flexible casing 46. A pair of thrust Washers 54 are provided betweenthe bit and the bearing surface of the thrust member.

Attention is directed to the orifice 55 in the bit and to the aperture56 in the hollow shank thereof; uid entering the tube 40 through theopening 51, as will be described presently, may move downwardly throughthis tube in the space surrounding the motor shaft, then downwardlythrough the fiexible casing 46 in the space surrounding the flexibleshaft contained therein and, after passing through aperture 56 and theshank of the bit, it will be expelled through orifice 55.

@hoelwgdgemis pivoted at 60 on the bottom piece I6 of the side drill.This shoe has a series of serrations 6I along one arcuate edge thereof,with respect to which arcuate edge the pivot 66 is disposedeccentrically, as shown. Connected to the shoe is a piston 62 adapted tomove up and down in the cylinder 63 under-control of fluid admitted tothe cylinder through a small pipe 64. The piston rod 65 extendsdownwardly through a suitable packing gland 66 and is bifurcated at itslower end to straddle shoe 59. By means of a pin 61 passing through aslot 68 in the shoe, movement of the piston will cause the shoe torotate about its pivot.

Below the motor but inside the casing I9 is a pump (not shown) which isdriven by the motor. The pump intake comprises a small flexible tubeextending downwardly in a loosely coiled helix and terminating in thechamber 1I. Amghgck .valve indicated schematically atlgmpyermits fluidto enter this chamber from outside the shell I4.` Fluid is expelled fromthe pump into chamber 13 through the outlet 14, and from chamber 13 itmay flow either through aperture 51 toward the discharge orifice in thebit as hereinbefore described or it may ow through the small pipe 64into the hydraulic cylinder 63.

In operation, my side drill functions as follows: The unit is loweredinto the bore hole to the desired depth by means of the cable 3|. If thewell is dry at the point to be drilled. liquid is in- 4 troduced intothe bore hole until the drill unit is entirely submerged. Orientation ofthe unit may be observed at the surface by means of a Selsyn motorconnected to the Selsyn motor of gyroscope 29 in conventional fashion.

When the side drill is at the desired level and is properly oriented,the motor I9 is started by means of a switch at the surface. Thereupon,the pump, drawing fluid into the lower chamber 1I through valve 12 andthence upwardly through tube 16, discharges it into the upper chamber13. Part of the fluid passes from the upper chamber through the opening51 and out orifice 55 as hereinbefore explained; the orifice is small incomparison with the capacity of the pump however, and consequentlypressure is built up in chamber 13 which forces fluid through tube 64and into cylinder 63. This pressure acting on piston 62 draws up theshoe 59 so that its serrated edge 6I rmly engages one wall of the wellcasing 16.

Cable 3| now is paid out slowly with the motor I9 still running. As thedrill unit moves downwardly, shoe 59 causes the lower end thereof tomove laterally and become wedged in the casing of the well in such a wayas to press the opening 45 firmly against the side wall of the bore hole(see Fig. 1a). If the cable 3| now is paid out still more, the motor andthe auxiliary casing 24 with the instruments contained therein will movedownwardly due to their own weight, driving tube 46 and the flexiblesleeve or casing 46 downwardly before them. The bearing 53 at the end ofthe latter casing accordingly transmits a thrust to the` rotating bit,causing it to advance through 4'the vcasing 16Mand intovthe side wallv'along the path indicated by'dotted lines in Fig.

1a. Spring 41 serves as a support to prevent the upper end of theflexible sleeve 46 from buckling under the compressive force actingthereon.

As it advances, the movement of casing 24 relative to the outer shell ofthe side drill unit causes reel 21 to turn and this progressivelychanges the setting of rheostat 28. The resultant change in resistancecontrols a milliammeter or other electrical instrument at the surface,enabling the operator to determine just how far the bit has advanced sothat he may stop drilling at any desired depth. The maximum depth ofpenetration is determined by the distance which tube 40 may travelbefore it is completely telescoped within sleeve 4 I. This obviously maybe increased by increasing the length of the tube, the sleeve and theassociated parts; if the distance between motor casing I9 and bottompiece I3 were made 30 feet, for instance, the bit could be advancedapproximately 15 feet into the side wall. For a penetration of 15 feet,tube 3D naturally would also have to be 15 feet long.

Throughout the advance of the bit the fluid expelled through the orificetherein assists in the drilling operation and flushes the cuttings backinto the well bore. A sealing ring 11 pro vided in a suitable annulargroove in bottom piece I6 engages the casing 16 of the well bore tobetter localize the circulating fiuid, whereby the cuttings returned tothe well bore tend to be drawn into chamber 1I through the intake valve12 and to settle in the bottom thereof around the hydraulic cylinder.

When employing my side drill in an uncased hole the same method ofoperation as described above is followed. In place of the shoe 59however a spade 59' preferably is substituted, as shown in Figs. 4 and5. Thisserves the same purpose as the shoe and functions in the samegeneral way, but it has a broad, somewhat sharpened edge 6I' which isbetter adapted than the shoe to dig into the side wall in order to wedgethe bottom of the side drill unit in the borehole. From the foregoing itwill be seen that this invention is one well adapted to attain all ofthe ends and objects hereinbefore set forth together with otheradvantages which are obvious and which are inherent to the apparatus.

It will be understood that certain features and subcombinations ofutility may be employed without reference to other features andsubcombinations. This is contemplated by and is within the scope of theclaims.

Inasmuch as many possible embodiments may be made of the inventionwithout departing from the scope thereof, it is to be understood thatlall matter herein set forth or shown in the accompanying drawings is tobe interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim: l. In a side drill for awell bore, a casing adapted to be lowered into the well bore, a rigid`guide tube in said casing having o-ne end opening toward the side wallto be drilled, a flexible sleeve having one end within said tube and theother end extending out of the tube into the body of said casing, aflexible shaft within said sleeve, a bearing rigidly affixed to said oneend of said sleeve, a bit supported by said bearing and attached to theend of said shaft, means to apply a force to said other end of saidsleeve in such a direction as to cause said bearing to transmit a thrustto said bit to advance same toward said side wall, means to supportother end of said sleeve comprising a spring coiled about said sleeveand a rigid tube encircling said spring, and mechanism to rotate saidshaft within said sleeve and hence rotate said bit as it advances.

2. In a side drill for a Well bore, a casing adapted to be lowered intothe well bore, a rigid guide tube in said casing having one end openingtoward the side Wall to be drilled, a flexible sleeve within said tubeand a flexible shaft within said sleeve, a bearing rigidly affixed tothe end of said sleeve, a bit supported by said bearing and attached tothe end of said shaft, an orifice in said bit communicating with theinterior of said sleeve, apparatus to advance said sleeve and shaftwhile rotating said shaft in said sleeve,

thereby to drill the side wall, a sediment chamber in said casing havingan inlet positioned below that end of said rigid guide tube which openstoward the side wall,` and pump means for drawing fluid into saidchamber through said inlet and driving it through said flexible sleeveto expel it through the orifice in said bit.

3. In a side drill as claimed in claim 2, a sealing ring encircling saidcasing at a point below said inlet and engaging the side wall of thewell bore to prevent drill cuttings from descending therebelow.

4. In a side drill, a casing adapted to be lowered into the well bore, arigid curved guide tube in said casing having one end opening toward theside wall to be drilled, a flexible shaft in said casing having at oneend a bit directed toward the side wall, mechanism to rotate saidflexible shaft and to advance it with respect to said rigid tube therebyto drill said side wall, a rheostat, mechanism to progressively changethe resistance of said rheostat as the flexible shaft advances withrespect to said guide tube, and electrical conductors leading from saidrheostat for connection to a device at the surface controlled on a cableto enable same to be lowered into abore hole, a casing enclosing saidmotor housing and movable relative to said housing and said cable in adirection axial of the bore hole, a rigid curved guide tube in saidcasing having one end opening toward the side wall of the well bore, aflexible shaft in said guide tube having one end connected to the motorshaft for rotation thereby and the other end connected to a bit directedtoward the side wall of the bore hole, a pump connected to said motor, ahydraulic piston operated by said pump, and a member on said casingconnected to said piston and operated by said piston to lock said casingin the bore hole at a h ereafter vadvanc'e's'f'"said flexible shaftthrough said curved tube to drill said side wall.

6. In combination, a vertically elongated casing adapted to be loweredinto a well bore, a partition in said casing dividing the same intoupper and lower compartments, a motor and pump rigidly connectedtogether to form an integral unit, means supporting said unit in one ofsaid compartments, said pump having its intake connected to one of saidcompartments and its exhaust connected to the other of saidcompartments, whereby they form suction and pressure compartmentsrespectively, a port in the wall of the suction compartment foradmitting fluid thereinto from the well bore, and a hydraulic ramconnected to said pressure compartment and operated by fluid underpressure therefrom, and a device actuated by the ram for engaging theside wall of the well bore to immobilize said casing in the Well.

7. In a side drill, a vertically elongated casing adapted to be loweredinto a well bore, a partition in said casing dividing same into upperand lower compartments, a motor and pump rigidly connected together toform an integral unit, means supporting said unit in one of saidcompartments for movement axially of the casing, a bit connected to themotor shaft by a flexible shaft, guide means for the flexible shaft tocause same to issue from the side of the casing and advance the bitlaterally as said unit moves axially in the casing, said pump having itsintake connected to one of said compartments and its exhaust connectedto the other compartment whereby they form suction and pressurecompartments respectively, and a port in the wall of the suctioncompartment for admitting fluid thereto from the well bore, said portdisposed below the level at which said flexible shaft issues from thecasing.

8. A side drill as in claim 7 including a flexible sleeve around theflexible shaft, said sleeve having one end adjacent the bit and itsother end communicating with said pressure compartment whereby the fluidpumped into the latter compartment flows through said sleeve to saidbit.

9. A side drill as in claim 7 including an annular dam around the casingbelow the level of said port bridging the space between the casing 'andthe inner wall of the well bore.

10. In a side drill as inclaim 7 wherein said unit is in the uppercompartment, a support connected to said unit and extending upwardlythrough an aperture in the top of said casing to the surface to carrythe weight of said unit, said casing being vsupported and carried bysaid unit during its descent into a well bore, and apparatus to locksaid casing in the well bore at a particular level whereby the continueddescent of said unit thereafter advances said flexible shaft rand bitlaterally.

11. In a side drill, a vertically elongated casing adapted to be loweredinto a well bore, partition means dividing the casing into upper andlower compartments, a motor and pump rigidly connected together to forman integral unit, means supporting said unit in the upper compartmentfor movement axially of the casing, a curved guide tube in the lowercompartment communieating at one end with the bottom of the uppercompartment and communicating at the other end with an aperture in theside wall of the lower compartment, a flexible shaft in said guide tube,said shaft having one end connected to the motor shaft and having a bitconnected to the other end whereby a downward movement of said unitrelative said casing causes said shaft to issue from said aperture andadvance the bit laterally, said pump having its intake connected -tosaid lower compartment and its exhaust connected to the uppercompartment whereby they form suction and pressure compartmentsrespectively, and a port in the wall of the suction compartment foradmitting fluid thereto from the well bore.

12. In a side drill for a well bore, rigid tubular 8 guide means havingone end directed towards the surface to be drilled, means for driving-abit member including a exible rotatable shaft and a surroundingnon-rotatable flexible sheath, said lexible shaft and sheath beingdisposed in said tubular guide means and terminating at said one end ina bit member positioned adjacent said surface, means to support theother end of said exible shaft and sheath within said tubular guidemeans comprising a coiled spring within said guide means and surroundingsaid shaft and sheath, and mechanism to rotate and advance said shaftand sheath thereby to drill said surface.

ARMAIS ARUTUNOFF.

REFERENCES CITED The following references are of record in the le ofthis patent:

